Depending on where you are based, give one of the people on this website a call and they can give you some unbiased free advice.
http://www.aerobatics.org.uk/training/buddy_main.htm The rest of the website might be of interest to you.
BTW, Aerobatics always seems expensive by the hour, but you fly much shorter flights than point to point flying so the actual £s are not that much more. For example my standard flight is 0.4-0.5 hr
Enjoy it, its very addictive and enjoyable and there is always something more to learn.