I have a firestick 2nd gen and it buffers a lot I have followed all the tips like clearing cache and even reinstalling. This doesn't happen on my phone, laptop or pc just the firestick. Is it the firesticks memory cap that is the problem because when I look at how much storage is being taken it is at 2.20 GB left but still buffers channels like NFL Gamepass, ESPN, and NBA channels
Although your device has a lot to do, it sounds more of an isp issue
Maybe the new upcoming Google TV ?
Could be a combination of wireless signal to the device, issues on the providers end or the stick itself. Depending on your service needs if it's m3u based everyone will tell you must spend an arm and a leg to buy an Nvidia Shield. From personal experience with both the shield and the Formuler Z8 I would lean towards the Z8 as it's able to use either m3u or mac based services. If gaming is a consideration then possibly the shield. Good luck.
Try a nvidia shield pro
It's not a storage issue as you don't save the streams onto your device, but only stream them. It's a spec issue, 2nd gen was released 4 years ago, time for an upgrade. To answer your question, Nvidia shield is the best device, but firestick 4k should be enough to watch IPTV.
Here's a suggestion. Forget the fireshits and buy an Nvidia shield. Enter of power and customer support.
Formula Z8 for me. Solid, powerful, epg is great and hassle free. Although if you already have a FS, that does the job just fine and I've experienced no lag, could it be the software you are using? It was my device before upgrading and could have happily kept using this tbf.
Try
nvidia shield pro
4K Firestick or the Buzz TV Stick use them both and they are great.
I have a Z8 and have been satisfied. If you are going to run other resource-hungry applications on the box such as kodi, the definitely go with the shield. The reason to buy the z8 is for mytvonline2. The hardware is mediocre. I just love MOL2.