Would the 1300 run my batch 7 miners tho? I've read the actual usage can sometimes spike up to 1400w on batch 7
1400 watts at the wall *0.9 (efficiency) = 1260 watts fed to the miner. You won't have any headroom for overclocking further but its "ok". I run my EVGA G2 1000 at 1000-1050w at the wall because i wish to be a tiny bit conservative, but if you already have the 1300, i'd go with that. Personally i like to keep my At the wall at up to what the thing is rated, for maximizing the lifetime of the PSU.
The downside is at close to 100% load you're not at 92% efficiency anymore. If you dont have a 1300 yet, you could look into something higher.
If you have more concerns about running the miner at 95% load, check the Johnyguru reviews.