Yeah, I occasionally get similar offers via Amazon. I never agree to their terms so I get those offers less often now.

In January I got a XOSS G+ minimalist GPS bike computer and within a couple of days got an offer to buy another half-price. No pressure to give a perfect review, just a discount as a bit of a carrot on a stick.

Setup was a bit tricky but other than a couple of glitches -- GPS sync taking 15 minutes or so, delayed uploads to Strava -- it's been good.

No more drain on my phone, I can see crucial data easily -- mostly heart rate -- and it's much smaller and lighter on the handlebar.

I'd give it 4 stars on Amazon, conditional on the basis that it's a very minimalist computer, no navigation aids, etc. But the data usually matches my phones, so it seems reasonably accurate.