I use a Garmin Aera 660 on a RAM mount; it’s perfect for helicopters. You can either plug it in or buy a second battery; you’ll get roughly 4hrs per battery.
With the European/US charts and the enhanced terrain downloaded it is great (I actually “dial down” the map detail). The screen is sharp/clear in sunlight and it’s quite simple to use.
Has some nice features such as GPS derived AGL for your location (a poor man’s RadAlt). I have SkyDemon and iPads like everyone else, but I find the 660 far better.