I'm struggling...I want to add a horse to the stable, but I'm just not sure which way to go! I've leaned from one side of the fence to the other so many times my head is spinning. Here's my delema. I have a old Jazz bass now, a Warmouth body (I think made out of Leadwood) with a Mightymite neck, EMG's and a Smith IV bridge, and I'm using Ernie Ball Power Slinky 55-110's because, well, fat strings feel good and I liked the purple package best. It has served me extremely well in previous years playing in an old school blues band, but I've got a new gig playing more of a eclectic rock mix (from Jefferson Airplane to Soundgarden) and I'm not getting the growl and sustain I think I'd like, find myself seeming to "run out of breath" on long held out low end hits. I know this is probably part of my problem but honestly although I've been playing a long time, I'm not much of a technical person...more so a "strap it on and thump it out - can somebody turn the nobs on this amp for me" player, and I don't have much experience (ok zero) with action set up either. I'm using a Hartke 5500 with a 410xl cabinet and borrowed no name 15" bottom. I've been quite happy with the Jazz, it plays well and the rig sounds fine, its just I'm losing the long notes pretty noticeably and I just dont feel I'm getting the bottom end bark like I want it, and any amount of tinkering doesn't seem to provide the results I'm satisfied with. Style wise, I'm rarely up the neck very far. I'm most comfortable pumping out the bottom end finger style and I couldn't slap my way out of a paper bag. Thus my dilemma. I'm going to add another bass to the mix, and I guess (more indecision) I've narrowed it down to a P Bass or Thunderbird based on the old school brand, body style, cool people who play them (yes I'm sure there are cool people who don't play them), research on what I think they can provide me, reviews and suggestions, etc. I definately want to stick with used...I have some wierd phobia about new stuff. I love the look of both basses, kinda have a Fender preocupation, but wouldn't mind something new and different. I don't have access to a close enough shop or a valid drivers license (doh!) to try one on in person, so this will be a remote purchase based on months of agonizing deliberation, craigslist and ebay watching, research, youtube reviews, culminating in the discovery of this awesome forum and maybe some of your input, as well as finally having the dough to pull the trigger. So, your thoughts on the subject would be greatly appreciated! Cheers!