Hi Adam,
get that plane finished, you.ll love it. I've just got standard servos in except for the ailerons which are 6.5Kg ones. with the rx and battery attached to to servo tray and the tank empty it balances 3 1/4" back from the LE with only the Saito '65 for front end weight. I'm using a muffler from a firm in the UK called Just Engines and it has a lovely quiet growl. With a 13x6 APC it's pretty fast but not excessively so I'll try and get it on video but the first attempt was a failure, my cameraman couldn't keep up with it! never the less he's gone and ordered one! I think I may upgrade the u/c to a carbon one but not at the moment as opposed to the trend it seems to be holding out OK although it has gone a little toe out. I fly on the fells on the edge of the Lake District where it's a little windy which isn't a problem, in fact it's a help to slow it down for landing. a Saito '80 would probably be nice but even with the '65 I can take off in about 25 feet and climb out at 45deg. Don't listen too much to the grumbles, the earlier ones don't seem to have been as well made, (especially the blue u/c) for the money (90GBP over here) you're getting an impressive little model.
Enjoy
Dave :^)