I am the owner of a vmar Bird Dog and a Subaru.
I am generally a foamy / electric fan cos I dont have much free time, and prefer to spend my time flying instead of building or fixing planes.
I cant comment on how they fare when powered by IC however I have been very happy with there flying characteristics and there repairability so far while powered by electrics.
They are a cheap plane to buy so do represent good value for money in my opinion if compared to more expensive brands that I have also owned and only noticed a modest improvement in quality.
So to all you vmar knockers out there who are so stupid to leave their planes and brains out in the sun all day ..... Find a shed or tree to put your plane under mate.
As for me I just got myself a new vmar twin otter and cant wait to build and fly it cos I know its guna fly great like my other vmar planes .