I have my 2nd project live on Kickstarter at the moment (
https://www.kickstarter.com/projects/68 ... -3-minutes). We are already at $54k at the moment, and we are trending towards 140k.
I am using Gadget Flow for a week or so and the results are great. I tested them out with the cheapest promotion and it was OK. ROI was positive but nothing to write home about. I upgraded to the 2nd most expensive package and It really boosted my sales as soon as first promos started hitting social media and e-mail.
Currently I have $5k of direct pledges from them and I am at least $1k more of assisted conversions (kickbooster says 3.5k but I think thats a bit too much). And we are still not even half way through our promotion. It looks like they will bring in at least 15k in pledges by the end of my campaign.
Also, your GF page will stay online which really helps with SEO and brings in some additional sales over time.
(Note: GadgetFlow is the only booster on Kickbooster)
I already recommended GF to some of my close friends and coleagues and some of them are already trying it out. My advice would be to go for a premium or platinum packages. I will use them again after Kickstarter campaign to boost my sales.