You did not include the model number, so we can't know exactly which Snapper RER you have in mind.
But, I own 2 of them (well, one of them is actually my wife's).
Hers is a 1968 Snapper comet. Mine is a 1986 model 28086S.
Both run well and cut grass well. They are fairly bullet proof little mowers overall.
They are also very maintainable by a handy homeowner if that home owner can read and follow instructions.
Those are my opinions of Snapper RER from my house.

Wapsiguy - another major factor is the "terrain" of your yard. Sharp inclines (>15 degrees), berms, number of obstacles and their concentration (trees, shrubs, flower gardens, etc.)
A relatively flat yard, few obstacles and the Snapper RER )if in good condition) will do nicely.
Lots of obstacles - would look for a small residential zero turn mower.
Sharp inclines/berms - invest money in either low maintenance ground cover or re-landscaping first before investing in riding mower/tractor.
JMHO...
But, I do concur with Mownie in his assessment of the Snapper RER's - tough and dependable, given normal care.

I have had my Snapper rear engine rider mower since 1983, when i bought it new! Re-powered it once, about 10 years ago, but still the original frame and running gear. I use it for mowing, cart hauling, leaf chopping and gathering, and a lot of other things. Replaced the main drive disc once, in all that time!
I have sold other machines, but always kept the Snapper. I also own an older model, which sits in reserve. Best mower to have and use, except for the raising up of the front end when starting up, heading up-hill. Especially with a full bagger! WHOOPEE!! But, i've never had it fall over backwards! Never!