Just saw that on zavvi and was intrigued but bought this for my OH, https://www.analogue.co/mega-sg no lag and can game on SMS and MD with an all in one cartridge off ebay.
When all else is equal, yes, but I'm pretty sure I'll have more fun playing an almost unlimited amount of roms, on a wide-screen TV, with 2 full-size arcade sticks, than you would have playing the handful of titles available on this tiny screen. Objectively, the Sega Astro City is very much overpriced for what it is. Still, you do you, and I'll do me.
I wouldn't say that it's horrible, but it does depend on the games you're playing. I'm a child of the 70's and a Pandora's Box plays the games of my youth perfectly well (Galaxians is still great!) and let's my daughter play a host of Neo Geo arcade games without any issues. I wouldn't expect it to run the arcade version of Mortal Kombat, of course, but it runs the home console ports of that game. I've been meaning to set up RetroPi for a few years but haven't got around to it, so spending £60 on a Pandora made sense for me. It's not perfect, but the box I picked up has 2 sets of nicely engineered arcade sticks and buttons, ~2000 installed roms, and provides a quick 'pick up and play' experience, while also acting as a USB arcade stick for a RasPi or PC (when I get around to setting up an Emulation box). It's the best £60 I've spent in some time.
Looks OK for £20 but around £100 better buying a ps vita for £50 and using that for emulators