Anybody done it? I have a early 9200T with a 500GB sata That is getting rather slow. I also have a 9150T My son isn't using any more. Would I be able to swop in the 500GB and retain the recordings and would I see any Performance gains?

I assume the 500GB drive in the 9200 is using an IDE to SATA converter? If so you could swap it but I think the file system format although similar is not identical so I wouldn't be confident that the recordings would be retained. I am not sure about performance. The 9150 may have a bit more RAM and a faster CPU but I am not certain.

The 9200T were all made using IDE. Some people have replaced thee with the easier to find SATA drives and sourced a suitable adapter that would fit in the 9200T case and I think used an equivalent Seagate SATA drive. Are you sure that your 9200T is now using a SATA drive?
Although the disk formats are very similar I doubt that if anyone has tried a transplant from a donor 9200T to a 9150T.

With respect to performance gains, the 9150T doesn't slow down as much as the 9200T when the epg is overloaded.
If you do not watch channels from all 6 multiplexes from your local transmitter then you could retune manually retuning with the aim of ending up being only tuned to 5 of your local transmitter's multiplexes. These days the 9200T copes with this a lot better than all 6 multiplexes , or even worse being tuned to more than one transmitter.

Edit: Pipped by Martin. I must type faster!

It's a converted one. Startech IDE to SATA Convertor and a Seagate Pipeline SATA 500GB hard drive. I might leave it until the 9200T starts giving problems. I use a FOX-T2 but my other half is the main user of the 9200.

Yes I agree that the tuning to a subset of multiplexes has helped a number of people; some only tune four multiplexes.

Oops! Agree. It would be four (or less) not the five I stated.