How effective is the SKYRC nitro engine heater? Will it help us get our RC nitro engines started?

A quick look at the SKYRC nitro engine heater - is it any good and does it do what it claims to do?
should you invest your hard earned cash into the piece of equipment that can used for nitro RC racing or throughout the RC nitro hobby.
Will it take away some of the stress and frustration when trying together your engine started - especially on those colder days!!!!