The biggest cost for machine work is labor for setup. Once the set up is done (properly), most any idiot can complete the process.
Balancing the cost of TRW press fit against the cost of having the work done...you are bucks ahead to sell them, even at a loss, and getting another set, rather than fool around with the ones you have.
As to whether its worth it or not...can't make that decision for you. Personally, I prefer full floater. There are a lot of guys that "mistakenly"
... like press fit. Seriously, I doubt if there is any real benefit, other than ease of assembly and personal preference. Spiral lock vs. "C" clips vs. press fit are something that will always bring up some debate. Best I can figure, It's just hard to break habits you learned when starting out, especially if they are successful over time. Why change a winning combination.
Personal advice: sell the pistons you have and get the ones you want .... or just use them as is. Futzing around with already done machine parts, unless you can do the work yourself (or you have a speed secret) is tossing money in the toilet, and we all know thats mostly what we are doing anyway...why throw extra into the privy?
<font size=-1>[ This Message was edited by: beoweolf on 8/28/06 2:56am ]</font>
for the majority of guys press fit are just fine. The cost to do a retro-fit is silly to be honest. Alot of guys like the press fit because they can potentially eliminate the cost and process of having the small end resized which is mandatory on aftermarket floating rods such as eagle and scat since they always come too tight. Just sell those on ebay, correct marketing and wording you will recover all your money.