So I know it has been a while, but I wanted to give a final update to my tank searching:
After deciding to start cave training later this year, I decided I needed to try and find the big steel tanks I had been searching for. I tracked down two separate Worthington HP130s on Craigslist, and purchased them. I then realized that not all Worthington HP130s are made the same, and that one was noticably shorter than the other! Thankfully my Instructor introduced me to the secret of "one boot doubles", and I had them matched up in height. Before putting a manifold on them, I did some test dives in the pool, and then at Hudson Grotto, using them as independents. They were ridiculously heavy out of the water, but felt pretty good to dive with, and they trimmed nicely. Although I realized my 35lbs doubles wing was not going to cut it (it was almost fully inflated at 110' with full tanks and not very comfortable! Plus it is designed for 7.25" tanks, not 8").
Fast forward a month or two and I take them to get VIPd and to put a manifold on them. One was beautiful inside, and one was full of rust!! (They hadn't been refilled since I bought them, so it was clearly this way not only when I bought it, but when the previous owner, a dive shop, slapped a VIP sticker on it!) Not happy with the situation, I managed to sell the good one after a fresh VIP, and I took the other one back and got a reluctant refund from the seller / dive shop (who had originally put the VIP sticker on the rust filled tank ...).
Ready to give up and resign myself to a life of tank rentals, I then stumbled across a pair of brand new never wet HP120s for $385 each. A diver had apparently bought them, decided they were too big, and then put them up for sale. This was way over my $500 budget, but I liked the idea of new tanks after my rust experience. I tried to find a pair to test in the water before I committed to the purchase, nervous about the extra length making me too butt heavy in the water. But the closest rentals were hours away. After much SB research about HP120s affecting trim (everyone seems to love them), I decided to just go for it. I managed to get the pair for $650 (very pleased!), and headed off to Blue Grotto...
..I love these tanks! I am 6'1 and they trim out beautifully, if anything I am a tad head heavy. They feel much better than the 130s did out of the water (the weight seems better distributed). I managed 4 dives and still had almost 1000 psi in each one! Only issues I found are that I will still need a bigger wing (but that was expected), and the rear D ring is hard but not impossible to clip a reel to.
All in all, HP 120s seem to be the fit for me! Thank you everyone for all your advice. I referred back to it several times during my search!
Also, I am currently AN/DP, and by the end of this year will be Intro Cave as well. If anyone would like a dive buddy in Central FL let me know!!