Please don't take this the wrong way but with a low price point it's a hard question to answer. The best thing to look for is a tub that you feel is a good value for you. As you read this I too had a low budget of $5000 and eventually paid around $6500 for the tub I own. At a $12,000 price point you have anything to chose from and that question would be more answerable. In 2004 a D1 Californian was selling for about $8000 here in NJ.
Look at Tiger River, D1 @home series, Marquis Everyday series, Sundance 700 series, Beachcomber 300 series, Artesian Island and maybe Emerald Spa or Down East. The Artesian, Emerald and Down East have configurable tubs that you may be able to get one under your price point. The Beachcomber was a lower priced spa in 2004
Lower end tubs tend to have smaller jets than their higher end versions. Marquis apparently have nice jets in them but you may not get them in the Everyday series.
We all choose different tubs because of various reasons - that's why a wet test may be important to you.