If the TekSavvy VoIP Service does not use your internet connection similar to Shaw home phone which has a separate phone modem, the added monthly cost may worth it as you are not dealing with the internet jitters affecting your voice quality.
Worth noting some more changes to their offerings:
Basic gain Caller-ID
Premium + Unlimited gain:
Screening List Editing: Screening List Editing allows a subscriber to manage the list of directory numbers to which a particular call treatment is applied, for example Selective Call Rejection.
Unconditional Call Forwarding: Forwards all incoming calls to a different number.
Busy Call Forwarding: Forwards incoming calls to a different number when the dialed number is busy.
Selective Call Forwarding: Forwards incoming calls from numbers selected by the subscriber.
Unavailable Call Forwarding: Forwards incoming calls to a different number when the dialed number is unavailable (for example if the telephone is unplugged or loses power, if a SIP subscriber is not registered or not contactable).
SimRing: Allows the subscriber to specify a list of numbers which are rung (in addition to their own number) whenever their line is called. Any of the numbers that are rung can answer the call.
Calling name delivery blocking: Calling name delivery may be blocked on a call-by-call basis as for Calling number delivery.
Automatic Recall (AR): Allows the subscriber to return the most recent incoming call.
Selective Call Rejection: Rejects calls from specified numbers.
Anonymous Call Rejection: Automatically rejects all calls from callers who have withheld their number.
Do Not Disturb: Allows the subscriber to block his or her line temporarily to prevent incoming calls. Outgoing calls can still be made as normal, but incoming calls are rejected with an announcement or forwarded according to the busy call treatment.
Reminder Call: Allows the subscriber to schedule reminder calls, either once or at regular intervals (for example daily or weekly).
Speed calling: Enables the subscriber to call frequently used numbers by dialing a short code. Both one and two-digit short codes are supported.