Don't forget Dr.bass. I think 3 way cabs are the end all be all.
drbasscabs.com
I have now heard 2 of them and I am waiting for my 2460 to come in.
You can find reviews on all the heads here. On thing that might helps some. In the blue bar at the top of the screan there is a search function link. Click it, then click "go advance" Type in thunderfunk and use "title only" and you will get some fair results.
What is most important
Volume? Weight?
Are you playing with horns and a loud PA, do you always have PA support?
I would say try acmebass.com and look at the LOW B 2.
Final answer to cover all situations.
A Dr. Bass 2460 in 4 ohms with the 1260(112 with an 6" mid driver) neo slant face or a 2060 neo cab(210 with mid driver). this way you can take either the small cab, the large cab, or both to a gig.
the 1260 on top in slant will make sure you hear yourself while the 2460 gets the sound to the audience.
As for a head, I think funk and jazz sounds would be somewhat aggressive. I vote for the Genz Benz GBE 1200. You can check out sound clips at genzbenz.com . Also, consider the Genz Benz 212 neo. I have heard many good things about it.
You will still be far below $4000 and have a fantastic Rig.
I suggest NOT getting a power regulator. If you get rack effects, no alesis. They are kind of noisy. I say try some pedals for any particular effect you need.
If you do go multi effect, I suggest line 6.
Hughes and Ketter makes an amazing tube drive pedal called the "tube factor"...yummy.
Oh, also get covers for any cab/cabs you get. Speakon to speakon 12 gauge speaker cables, a right angle - straight 20 footer for you with a spare. And a folding dolly.
http://www.handtrucksrus.com/crashdetail.aspx?id=480
http://www.handtrucksrus.com/crashdetail.aspx?id=461
No monster cables IMO.
hmm, a good rack, no rack bags unless you get a very light head.
And with the money left over an all tube head is a must. If I had extra cash right now I would get a small head like a Little Mark II and an all tube head like the ampeg SVTII (non pro), or Ampeg SVT CL.
I disagree with bergantino IP cabs. I have not been impressed with bergantno cabs...and for the price its just not that cool. Buy light gear if you can. Epifani cabs are nice...and light.