I am not sure if edits show up in the alerts people get, so I figured a new comment made sense.
When auditioning bows first and foremost you have to look at them as a player. I am a strong believer in getting your hands on as many bows as you possibly can within your limiting factor(s) which is usually cost, but geography and time can also be an issue and narrowing down from there. While developing your own understanding of preferences for certain characteristics in a bow, you have to have a few in your hands.
The fact that one of these bows isn't hands down winning makes me feel like you should keep looking. You have good things to say about both bows, but you also have reservations and in a perfect bow shopping scenario, one of them is going to stand out from all the rest as YOUR bow. That can happen in almost any price range and will be unique to each player and instrument. If you have access to some more bows you might find the one, and if not you will be developing a sense of what your preferences are to help narrow down your search. With that said, there are a few things that can be changed fairly easily for not an excessive amount of money and that can make a difference.
Hair: Even if it is never played hair gets dry and brittle and needs to be replaced every year or two. This can be responsible for wispy, and scratchy sounds or inarticulate attacks. Likewise if you prefer white or black hair and the bow has the opposite, certain assumptions can be made on what it will sound like with the opposite. This is a bit of a gamble, as some bows are slower to respond or scratchy sounding no matter what, and sometimes a new rehair in your preferred hair colour can make a world of difference. If I am auditioning a bow that is in need of a rehair, I try to remove as much of the rosin that is on the bow with a clean dry rag or new dry toothbrush, apply a moderate amount of my preferred rosin of choice, and play some whole note scales. I am listening for wobbly sounds that could indicated a flat spot/camber issues, (more on that in a second) if the bow sounds dramatically different across the range of the instrument, and if I like the sound. With that information, I can feel pretty confident I know what a new rehair is going to result in.
There has been a lot of good discussion here about the differences between black, white, and some of the other hair options, and a search should pull up some good reading.
Weight and Balance: This is one of the first things that turns people off a bow, and one of the easier things to adjust. While bass bows come in a variety of different weights and you are never going to have a 200 gram bow feel like it is 120, if a bow feels tip or frog heavy it is usually because of balance not weight. When a bow sounds great and has all of the other characteristics you like, talk to the bow maker or person helping you. Most shops will have some lead tape or something else heavy that you can use while trying the bow to give you a sense of what it would feel like with an adjusted balance point. That can be remedied by changing the winding about 85% of the time, 10% of the time something more dramatic like changing the tip to a heavier/lighter material or adding some lead into one of the mortises is needed, and maybe 5% of the time (usually on cheap factory bows) the balance is way too far out of whack that moving on to the next bow really is the best option.
Camber: Some bows have more camber in them than others. A lot of the time bow makers find a camber they like and each of their bows will be very similar to that, but sometimes the individual stick or the model of the bow dictates that more or less is necessary. There are fantastic and horrible bows on either end of the spectrum. Flat spots are worrisome, and can be difficult to see. Play some long tones and see if the bow skips or wavers. If that happens in the same spot every time, usually that indicates a flat spot. Also try starting the bow in both directions along the stick from frog to tip. It is most difficult to get and maintain enough camber right behind the head of the bow and under the winding in front of the frog, and if the bow does not start well in either place that could be why. You also want to have a look down the bow when it is at tension to make sure it isn't warped left of right.
For a variety of reasons a shop or maker might decline to alter the camber of a bow. Adjusting camber is one of the more dangerous repairs to do, but it can make a world of difference. I would stay away from a warped bow or a bow with a flat spot if the shop/maker will not fix it for you.
Previous/necessary repairs: This is more of a concern with pedigree/older bows, but worth mentioning. Good repairs are going to be challenging to spot, but can greatly alter the value of the bow. If you do see repairs ask if that shop/maker performed the repairs and see what they can tell you about them. A head spline, head/butt graft, or otherwise repaired broken stick loses the majority of its resale value. Other repairs such as a new tip or replaced pearl dots are far less significant provided they were done well. A bow in need of repairs is not a write off, but be aware of what that repair could mean down the road when you look to sell the bow.
Sound: Does it sound good from the top to the bottom of your bass? Is it balanced, or do certain registers pop out/die? Can you get a variety of different sounds out of it, or is it a one trick pony? What about dynamic range? There are tons of other questions to ask about sound. Some bows and instruments get along swimmingly, others really don't. I strongly suggest trying bows on your own bass for that reason. It might be the best bow for you and sound amazing on the bass at the shop, but that doesn't mean it agrees with your bass at home.
Wow, that ended up being a lot. To get back to the bows you are currently looking at, if the Dorfler is working well for you and you think a new rehair and potentially a different rosin choice is going to push it into "I have to own this bow" territory, then go for it. If not, I would suggest you broaden the search.
