CAN WE FOLLOW "IBADI" FOR FARD PRAYERS??

Assalamu Alaikm, Myself Abdulla safwan ,I am living in Oman and the muslims here are having "IBADI" aqaeda,the place where I live is 100% masjids with same people and I dont see any difference in their actions from ahlusunna. Searching and finding a masjid with imam not from ibadi background is very difficult here(or barely possible),we will understand the imam is ibadi at the end if it's a big jamath(they only make one salam to end the salah),or we can identify from their qiyam as they dont tie their hands. These are the only difference from ahlusunnah I found in them- in action kindly share the knowledge what should I do in this situation.and it will be better if a short detailing about Ibadi is possible. Jazakallah khair.

Ruling regarding them can only be issued after knowing their belief from any authentic sources.
From Kitabs,  we come to know that many of their beliefs are different from the beliefs of ahlu-sunnah wal jama'ah. 
Some of them are explained below;

1) A person will be in hell for ever, if a person commits major sin and die without making tauba.
2) Nobody will intercede for a person who committed major sins and died without making tauba.
3) None of the believers will see Allah in akhirah.
4) Meezan, Sirath bridge etc.. are not considered as real, but lame explanations are given.
5) Those who die without believing in Abaad will be in hell forever.

One of the famous scholar from Abubakar bin Abdillah wrote : I guarantee that one who died without the belief of Abaad will be nasty, unworthy & will be in hell for ever.
(Al Jouharul Muqthasar-121)

If Omani Abadis have these beliefs, then it is not permitted to follow them in salah.
If they dont consider Muslims who don't have the same beliefs as them to be kafir, then it is karahat-u-tahreem to pray behind them; even though the prayers will be valid.