Superb quality, good features and affordable price.
Grandstream appear to have really upped their game. I used an old Budgetone BT100 for years, which was OK, if nothing special. The new GXP-1620 is in a different class though. It feels like a quality product - very well finished with nice plastics and a pleasing appearance. Performance is excellent, and with provision for two separate SIP accounts, it's versatile, too. One thing I really like is the ability to sync my Google contacts with the phone, albeit with a third-party script. There are probably lots of features that I don't use; the bottom line is that this is a great phone, recommended without hesitation.
Overall, is worth money if you want spending less like other brands. Make a good job, sound is perfect clear both ways. Configuration is also easy. Display also is clear to read. My point of opinion about display, could by bit better but phone is for make a calls not reading from display 😁 and does their job well.