I own an Orion II, but know little of the 7300. Which is better for you depends on what your requirements are. The Orion does not cover 6 meters - do you want that? The spectrum scope in the Orion is about the worst ever in an HF rig. You can make it one of the best in that regard by adding the 9 MHz IF tap and an LP-Pan and sound card and NaP3. Can you do that? Another typical failure area in the Orion is the encoders used for AF level, RIT, XIT, passband tuning, bandwidth, etc. You can buy replacements at very low cost from Mouser, but the installation is a bit of a project - are you able to do that? The Orion II is a great rig for CW, SSB and the digital modes, but there is virtually no technical support available in case of failures. Tentec is closed down because of the virus and who knows if they'll ever open again.
73, K8AC