I got an excellent price on a plan through RVProtection.net. I don't normally buy such things, but I got a deal too good to turn down when they were having a promotion to gain a broader customer base. You might check there and also with WarrantyExperts.com. Nothing wrong with the GS plan either.
It is always less expensive in the long run to self-insure (pay as you go) as long as an unexpected big expense would not crash your budget. Put $1500 or so in the bank (hide it in a separate account somewhere) and use it to pay for any major expenses, should they occur. However, if you feel more comfortable having repair insurance, shop around for the best price because there is a lot of difference - as much as 100% in many cases.
You might also consider a plan with a deductible, where you pay for smaller expenses and have insurance only for big stuff, maybe over $250 or $500. There are a few of those around and sometmes are offered for older RVs.
I would not buy the individual warranties from individual appliance vendors, e.g a Dometic refrigerator warranty. They are fairly expensive and do you no good if your transmission fails instead of the fridge!
Since it is impossible to predict what thing may fail in a complex RV, broad coverage is probably better than targetted stuff.