Like De Sisti I didn't vote, because I chose rollers and a Concept2 rower (with PM5 monitor) instead. The rollers are an older, metal-framed version of the Elite Arion, which you can now buy for double the price I paid. I use these in an unheated garage in winter. In summer I ride a bike on the road.
For me it's a better alternative because:
The rollers allow me to train pedalling and balance. I use a Tabata timer mobile app to practise cadence intervals with rest phases. During the rest phases I ride no-handed, one-handed, and single-leg drills. The rollers also allow me to warm up before rowing.
I like that the rowing machine is just an erg, because I don't need the motivational aspect of Zwift etc, and it's easy to track training progress. I can just formulate a winter training program and test my fitness by attempting PBs over various distances later in the schedule. It's cheap - no subscription required and Concept2 hold my training log in the cloud. Also it trains my upper body to a greater degree than a turbo trainer.
To counteract boredom I use the mobile Spotify app with Jabra wireless earbuds.
I didn't post to start a heated debate or flame war about turbo trainers vs. rowing machines. Rather I wanted to point out that there is at least one alternative and my reasons for choosing it. It suits my age, preferences and budget. I'm a male and receive my state pension in 1 month's time. I need to counter increasing muscle loss and lack of balance between now and my actuarially-predicted demise at 86.