I can't tell you about reliability first hand, I will have mine for a year at the end of June, but I will be watching this conversation to see if there's more input from others.
What I can tell you is that since buying my tractor I have read more treads here on TBN than I can count about GCs and the following is my condensed version of all of it.
GCs have been around a long time. I've learned that a GC is a GC, they are basically all the same when it comes to the major stuff. Maybe not exactly, but you can look at any conversation about any GC to get an idea of the things people have issues with. They have the same engines and transmissions. The GC2600 is comparable to my GC1725M. So if you're looking at reliability you can go back a very long time on this forum and not find much in the way of big issues.
There have been some real issues, like the one about the control brackets on the backhoe:
Backhoe - Broken Joystick after 10 Hours (GC1725M/CB65) (I don't have a backhoe, but read it with interest anyway), but it seems that overall they do not have any more issues than other tractors considering that less people seem to own them then some other tractors, at least by reading and following TBN.
Most of what I've read I would personally consider minor, the kind of stuff I would expect would happen unless you leave your tractor parked i the barn and never use it. If you use a tractor things are eventually going to start to wear out
A lot of the issues I've read, major and minor, seem to be self inflicted wounds, stressing to me the need for proper maintenance. That goes for all brands and not just Masseys. It's simply amazing to how many people spend this kind of money on any tractor, expect it to last and then do things like never check the oil in the first 50 hours of operation or do any of the other routine checks.
As far as price of parts goes, the only things I've really had to by so far are filters. Yes, I use the OEM filters. They are a bit pricey, but not something I'm going to skimp on. I did have to buy a new fuel cap because I forgot to put it back on and drove over it and that cost me over nearly 50 bucks including the shipping. I'm willing to bet that prices are not much different than other brands.
Like
@Nacademus says, we're all at the mercy of the dealer, it's not like car parts where you can easily get replacement parts without going to the dealer to get them. Yes, you can get aftermarket replacements for things like filters for some of the others, but I probably would not do that anyway, no matter what brand of tractor I owned.
One of the good things I find about the GCs is that they all use the same engine and transmission. Most of the major parts are all the same, unlike other makes that seem to use different ones in almsot every model. This was one of its selling points for me because it means it should be easier to get the parts if they are needed.
