TV Renaisance eyepeices

Hi folks,
I'm new to astromart, but not astronomy. About 15 years ago I bought a TV Renaisance at an auction without an eyepiece. Since then, I've been using it with a mix-n-match set of eyepieces I've acquired including an Orion 32 ortho 2", 25 JSO ortho, 12 JSO Kelner, and a 7.5 Parks gold series. Alas, no TV eyepieces. I no longer have the JSO eyepieces as they were sold with another scope. I've been told that I should consider getting a couple of TV eyepieces. I'm now at the point where I'd like to invest in a couple of TVs. My question is this. If I were to have only two EPs to use with this scope, which should I consider? I've been thinking about a 12mm Nagler and a 4.8mm Nagler. I'd like to be able to do some planetary viewing and I figure the 4.8 combined with the 550mm focal length of the scope should give me sufficient power, but will I suffer chromatic abberasion with this high power EP on such a fast scope? If so, will stop down help?

Any opinions are appreciated.
Thanks

Hi Joe
I'm in a simular situation with a TV101 f/5.4 540mmFL. Getting high power out of these things is tough, small jump in eyepiece FL is a big jump in Mag. A while back I bought a 13mm T6 and it is a great eyepiece and it convenced me to convert to Naglers. With a good finder you should be able to get most targets in the FOV with the 12mm. I've never looked thru a 4.8.. but from what I've heard from others is, while it is a good eyepiece but it is one of the original Nagler designs and the T4/5/6's are much better. I did pickup a 7mm & 5mmT6 and both are excellent. I've been bitten by the Nagler bug. Naglers are not a curse, they are the cure!
Hope this helps
Buck