EMS - is it just a gimmick? anyone tried it?

[UntilYourNextHairBrainedScheme]

I have Tuesday afternoons off work to take one of my children to a weekly physio appointment - I drop DC off and I sit outside in a car park shared with a small gym/ fitness studio specialising in EMS, claiming general fitness benefits and especially that it's good for the back.

I've had back niggles on and off for decades - nothing terrible and have only needed a few days off work once, but sometimes I have to adjust my routine/ way of doing things for it (it's especially bad if I sit for too long).

I'm also trying to lose weight.

But it's not cheap and after a trail week involves a contract.

Gimmick or great? Any idea?

I am doing it but refused to sign the contract. So I just pay GBP30 by credit card for each session there and then. After 4 sessions I feel I have stronger back muscles. Its slow change, mainly toning and I think for sustained benefit needs to be supplemented with other exercise.