Hi Janelle, that is a very tough question...one should know exactly both products (in details) to provide you a like-for-like comparison. I'm not an expert about Solarwinds Orion neither about Aruba Airwave (I use HPE IMC and, concurrently, LibreNMS) so I can't really be of help...but, just a consideration...if you're looking for a NMS specifically tailored around HPE Aruba devices (where the N of NMS really means Network, thus not necessarily an NMS engineered to be the "Swiss Army knife" for any Servers and any Application management and monitoring)...and I mean...that's quite true when you have a lot of Aruba wired and wireless devices to monitor and manage in your network...typically it happens in campus scenarios...probably a NMS developed by the same Vendor of your devices is (a) a lock-in (Vendor tends to focus centrally on managing its devices avoiding to enlarge the application capabilities and features against 3rd party devices/applications...limiting the perimeter of action of its tool) but it is also (b) a very efficient tool (because it is engineered to be effective in monitoring and managing exactly those devices the Vendor develops, sells and supports...so it can't be in a better position when it develops its NMS application).
If Aruba Airwave fits your needs in terms of monitoring and management it could be really enough...but if you're looking for a NMS open to everything as the Solarwinds Orion looks like it is...maybe the latter is better than the former (again: IMHO they can't really be compared like-for-like).