I don't see why it would be an issue operationally. If your goal is to earn RDM/PQD/PQM then I would reference the below link and make sure your fare class is covered.
https://www.united.com/cms/en-us/mar...spx?itemid=379
Fare classes which earn RDM based on MP status
Fare classes A, B, C, D, E, G, H, J, K, L, M, N, Q, S, T, U, V, W, Y and Z are eligible for accrual
The PQM miles table show fare classes C, D, J, Z will earn PQM at the normal non-bonus rate