The landlord would much rather sign a lease with 4 real people than with an entity (company, partnership etc.). In fact, even a commercial lease to a limited company is likely to require the personal guarantees of the directors if at all feasible. Every landlord at this stage is wide to the problems of chasing debts from failed limited companies-it's hard enogh chasing debts from real people.
It is then the problem of the person who wants to leave the building which is much harder to resolve as they have signed a lease with the landlord and if later on the rent goes into arrears, that person is still liable as one of the leaseholders.
You might get lucky and find a landlord who will allow the entity to sign/seal the lease but I wouldn't as a landlord take that deal. Landlord might have property in an undesirable area, no good for commercial (off the beaten track, no road frontage etc.) and that landlord might be a bit more 'motivated' to get his property let to someone, anyone, anything!