As srf2112 says the 6X10 is good for coverage and is not all that heavy to swing. It also, due to the DD pattern, slips through trash fairly well for its size. If you read through a number of posts on different forums involving MXTs etc. you'll read where quite few folks that use the 6X10 as their most used coil, myself included. I was fortunate enough to make a good purchase on a clean, used MXT complete with the 4X6, 5.3 and 9.5 coils all on extra rods several years ago. I've added a 6X10 and a 12" to it since. I use the 9.5 and the 12 the least unless I'm hunting an open, fairly trash free area. Most of the time the 6X10 suits me very well. If the trash is a bit on the heavy side or sometimes just because, I'll use the 5.3. If I'm hunting a very trashy area and have the patience to cover a small area well, I'll put the 4X6 on. It really handles heavy trash well, but you pay for it in lost coverage and some depth. The coil selection is one of the MXT, M6 etc.s strong points in my opinion as it really adds to the versatility.
BB