I'd take two repellants. Something like Jungle Formula which contains DEET and Avon Skin so Soft. The DEET one is very good but IMO a truly horrible concoction -it melts plastic, stings if it gets in the eyes and numbs your lips. Avon Skin so Soft, I find, does not last as long but is much more pleasant to use.
Almost impossible to say if there will be midges then. First week in May is a bit early for them but it has been a mild winter in the NW and the last few weeks have, apart from about four splendidly hot days, been fairly wet (in Gairloch it rained for 13 hours last Wednesday). If there is a warm spell soon there could be some around.
Midges are a small price to pay for such a great area.
Thans Dave
I agree with your last comment. I have been to NW Scotland many times but up till now always in Autumn.
I know from experience that wherever there are midges/mosquitoes I seem to be a target and my skin does not react well!
Dave